1) To determine the adequate maintenance dose of CPZ in the chronic schizophrenics. 2) To compare the in-hospital plasma levels of patients and their levels as outpatients on same dose. Since we have shown that in most patients plasma levels appear to correlate with clinical improvement, then it would be important to see if the kinetics of absorption metabolism in chronic patients in state hospitals are different from the acute psychotics we have been studying. Our preliminary observations on plasma levels on chronic patients are extremely low compared to acute psychotics on similar doses. It is important to see if low levels are adequate for chronic patients. If so, what is the optimum level and what level and what kind of dosage will achieve this level. For the outpatients, ti is important to see if compliance is a problem and if so, it will be interesting to maintain outpatients with parenteral fluphenazine deconoate and measure fluphenazine levels and determine the adequate maintenance dose based on pharmacokinetics of fluphenazine in these outpatients. 3) We will stuty the relationship of cerebospinal fluid fluphenazine and plasma fluphenazine in psychiatric patients. This project is in collaboration with Dr. Roy Ginsburg from Stanford University. 4) More patients will be studied in lithium-CPZ interaction, following the procedure described in the protocol in Artane-CPZ interaction of this grant. 5) Mechanism of lithium-CPZ interaction will be studied in animals. BIBLIOGRAPHIC REFERENCES: Rivera-Calimlim, L. Impaired absorption of chlorpromazine in rats after chronic treatment with trihexyphenodyl (Artane). Brit. J. Pharmacol., 56: 301-305, 1976. Kerzner, B. and Rivera-Calimlim, L. Lithium and chlorpromazine interaction (Abstract). Clin. Pharmacol. Therap., 19: 109, 1976.